Marsh marigold (Caltha palustris) in UV (ultraviolet) light (bottom) and in daylight (top). The pattern seen in the bottom image, known as the bull's-

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Marsh marigold (Caltha palustris) in UV (ultraviolet) light (bottom) and in daylight (top). The pattern seen in the bottom image, known as the bull's-eye or nectar guide, is thought to help attract pollinating insects, which can see in UV light.

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Photo credit: © CORDELIA MOLLOY/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: biological, biology, botanical, botany, bulls, bulls-eye, caltha, cup, daylight, eye, flora, flower, flowers, guide, insect, king, light, marigold, marsh, natural, nature, nectar, palustris, pattern, plant, pollination, ultraviolet, uv, visible